Substrate processing apparatus and method for manufacturing semiconductor device using the same

ABSTRACT

A substrate processing apparatus including a chamber accommodating a substrate; a substrate support in the chamber, the substrate support supporting the substrate; a gas injector to inject an oxidizing gas for oxidizing a metal layer to be disposed on the substrate; a cooler under the substrate to cool the substrate; a target mount disposed on the substrate, the target mount including a target for performing a sputtering process; and a blocker between the target and the gas injector, the blocker shielding the target from the oxidizing gas injected from the gas injector.

CROSS-REFERENCE TO RELATED APPLICATION

Korean Patent Application Nos. 10-2016-0116795 and 10-2016-0151867,filed on Sep. 9, 2016 and Nov. 15, 2016, respectively, in the KoreanIntellectual Property Office (KIPO), and entitled: “Substrate Processingapparatus and Method for Manufacturing Semiconductor Device Using theSame,” is incorporated by reference herein in its entirety.

BACKGROUND 1. Field

Embodiments relate to a substrate processing apparatus and a method formanufacturing a semiconductor device using the same.

2. Description of Related Art

A sputtering apparatus may be used to deposit a thin film to form amagnetic tunnel junction (MTJ) structure for an MRAM device. In the MRAMdevice, a switching current may be applied to the MTJ structure toswitch a magnetization of a free layer (FL) included in the MTJstructure.

SUMMARY

The embodiments may be realized by providing a substrate processingapparatus including a chamber accommodating a substrate; a substratesupport in the chamber, the substrate support supporting the substrate;a gas injector to inject an oxidizing gas for oxidizing a metal layer tobe disposed on the substrate; a cooler under the substrate to cool thesubstrate; a target mount disposed on the substrate, the target mountincluding a target for performing a sputtering process; and a blockerbetween the target and the gas injector, the blocker shielding thetarget from the oxidizing gas injected from the gas injector.

The embodiments may be realized by providing a substrate processingapparatus a chamber accommodating a substrate; a substrate support inthe chamber, the substrate support supporting the substrate; a coolerunder the substrate to cool the substrate; a gate disposed to be movableon the substrate support in the chamber and operated to selectivelydivide the chamber into upper and lower chambers; a gas injector toinject an oxidizing gas for oxidizing a metal layer on the substrate;and a target mount facing the substrate and including a target forperforming a sputtering process.

The embodiments may be realized by providing a substrate processingapparatus including a chamber in which a substrate is accommodatable; asubstrate support in the chamber and on which the substrate issupportable, the substrate support including a cooler therein; a targetmount facing the substrate support, the target mount including a targetfor performing a sputtering process that forms a metal layer on thesubstrate, a gas injector to inject an oxidizing gas that oxidizes themetal layer on the substrate; a blocker between the target and the gasinjector, the blocker shielding the target from the oxidizing gas.

BRIEF DESCRIPTION OF THE DRAWINGS

Features will be apparent to those of skill in the art by describing indetail exemplary embodiments with reference to the attached drawings inwhich:

FIG. 1 illustrates a plan view of a substrate processing system inaccordance with example embodiments.

FIG. 2 illustrates a cross-sectional view of a substrate processingapparatus of a substrate processing system according to an exemplaryembodiment.

FIG. 3 illustrates a perspective view of an electrostatic chuck of asubstrate processing apparatus according to an exemplary embodiment.

FIG. 4 illustrates a cross-sectional view of a substrate processingapparatus in accordance with example embodiments.

FIG. 5 illustrates a plan view of a substrate processing system inaccordance with example embodiments.

FIG. 6 illustrates a cross-sectional view of a substrate processingapparatus of a substrate processing system according to an exemplaryembodiment.

FIG. 7 illustrates a perspective view of a gate in a housing of asubstrate processing apparatus according to an exemplary embodiment.

FIG. 8 illustrates a cross-sectional view of a showerhead movingtogether with a gate of a substrate processing apparatus according to anexemplary embodiment.

FIG. 9 illustrates a cross-sectional view of a substrate processingapparatus in accordance with example embodiments.

FIGS. 10 to 13 illustrate cross-sectional views of stages in a method offorming a memory unit of a MRAM device in accordance with exampleembodiments.

DETAILED DESCRIPTION

FIG. 1 illustrates a plan view of a substrate processing system inaccordance with example embodiments. FIG. 2 illustrates across-sectional view of a substrate processing apparatus of thesubstrate processing system of FIG. 1. FIG. 3 illustrates a perspectiveview of an electrostatic chuck of the substrate processing apparatus ofFIG. 2.

Referring to FIGS. 1 to 3, the substrate processing system 10 mayinclude a load lock chamber 20 for loading and unloading a substrate,e.g. a wafer, a transfer chamber 30 having a transfer robot 40 fortransferring the substrate, and a plurality of process chambers 50, 60,62 and 100. The transfer chamber 30 may be at a side of the load lockchamber 20. The plurality of process chambers 50, 60, 62 and 100 may beat sides of the transfer chamber 30.

In an implementation, the substrate processing system 10 may be used tomanufacture an MRAM device on the wafer. For example, the substrateprocessing system 10 may be used to form a metal oxide layer on a freelayer FL of a magnetic tunnel junction (MTJ) structure.

The load lock chamber 20 may receive a wafer from a wafer carriersupported by an index module, and the wafer in the load lock chamber 20may be transferred into one of the process chambers 50, 60, 62 and 100by the transfer robot 40, respectively. The transfer robot 40 may alsotransfer the wafer in the process chamber into the load lock chamber 20,and the wafer in the load lock chamber 20 may be transferred back to thewafer carrier on the index module.

The plurality of process chambers may include, e.g., a depositionchamber 50, a cooling oxidation chamber 100, a first additional chamber60, and a second additional chamber 62.

The deposition chamber 50 may be a sputtering chamber and may be usedfor forming a metal layer on the wafer. For example, the depositionchamber 50 may be a radio frequency (RF) sputtering chamber that iscapable of performing a physical vapor deposition (PVD) process using aRF power source. A target and a substrate stage may be provided in thedeposition chamber 50. After mounting the wafer on the substrate stage,materials ejected from the target may be deposited on the wafer by asputtering process. The deposition material may include heavy metals,e.g., tungsten, platinum, or bismuth. The wafer, on which the metallayer is formed, may be transferred into the cooling oxidation chamber100.

The cooling oxidation chamber 100 may be a substrate processingapparatus that is used for oxidizing the metal layer on the wafer at alow temperature. Hereinafter, for convenience of explanation, thecooling oxidation chamber will be referred to as a substrate processingapparatus.

Referring to FIG. 2, the substrate processing apparatus 100 may includea chamber 110, a substrate support 120, a cooler, and a gas injector.The substrate support 120 may be in the chamber 110 and may support asubstrate, such as a wafer W (e.g., the substrate support 120 may besuch that a wafer W is supportable thereon). The cooler may be in thesubstrate support 120 and used for cooling the substrate. The gasinjector may be used for injecting an oxidizing gas that oxidizes themetal layer on the substrate.

In an implementation, the substrate processing apparatus 100 may be usedfor oxidizing the metal layer formed on the substrate, such as a waferW, to form a metal oxide layer. The metal oxide layer may be formed on afree layer pattern of a magnetic tunnel junction (MTJ) structure to helpreduce a switching current density. The metal oxide layer may include anoxide of a metal having a large spin-orbit coupling. For example, themetal oxide layer may include an oxide of a heavy metal, such astungsten, tantalum, platinum, or bismuth.

The chamber 110 may provide a space, in which processes for treating thesubstrate are performed. The chamber 110 may be formed of, e.g., ametal. The chamber 110 may be grounded. An exhaust port 114 may beprovided in a lower portion of the chamber 110, and an exhauster 116 maybe connected to the exhaust port 114 through an exhaust pipe. Theexhauster 116 may include a vacuum pump, by which an internal pressureof the chamber 110 is adjusted. In an implementation, gases in thechamber and reaction by-products generated during a process may bedischarged to an outside through the exhaust pipe.

The substrate support 120 may include an electrostatic chuck 122 as anupper plate for attracting or coupling with the wafer W using anelectrostatic force. The electrostatic chuck 122 may include anelectrostatic electrode 124 that receives power from an external powersupply and applies an electrostatic force to the wafer W. For example,the electrostatic electrode 124 may be electrically connected to a DCpower supply. In an implementation, the substrate support 120 maysupport the wafer W using a mechanical clamping mechanism.

The substrate support 120 may include an electrode plate 130 as a lowerplate under (e.g., supporting) the electrostatic chuck 122. Theelectrode plate 130 may have a disk shape corresponding to a shape ofthe electrostatic chuck 122. The electrode plate 130 may include aconductive material. The electrode plate 130 may be grounded orconnected to a high frequency power source.

The substrate support 120 may include a lift pin 126 that is used forlifting the wafer W on the electrostatic chuck 122. In animplementation, the substrate support 120 may include a driver to movethe electrostatic chuck, e.g., upwardly, downwardly, and rotatably.

In an implementation, the substrate support 120 may include aring-shaped focus ring 128 that is disposed on or an (e.g., outer) edgeregion thereof. The focus ring 128 may surround an edge region of thewafer W.

The cooler may be disposed below the wafer W and may cool the wafer W.The cooler may operate to keep the wafer W at an extremely lowtemperature or relatively low temperature. In an implementation, thecooler may operate to keep the wafer W at a temperature of, e.g., lessthan about 298 K. In an implementation, the cooler may employ arefrigerator 310 that is used in a cryopump.

In an implementation, the cooler may include a cooling plate in theelectrode plate 130. The cooling plate 300 may include a cooling channel302, through which cooling fluid flows. The refrigerator 310 may beconnected to the cooling channel 302 to supply the cooling fluid to thecooling channel 302. In an implementation, the cooling plate may includea cooling surface in direct contact with a lower surface of theelectrostatic chuck 122. For example, the cooling plate may absorb heatfrom the electrostatic chuck 122.

The cooler may include a cooling gas passage 304 in an upper surface ofthe electrostatic chuck 122 (e.g., adjacent to where the wafer W is tobe accommodated). The refrigerator 310 may be connected to the coolingpassage 304 to supply a cooling gas to the cooling passage 304. Thecooling gas may be in contact with a surface of the wafer W, and thus, atemperature of the wafer W may be kept at the extremely low temperatureor relatively low temperature. In an implementation, the cooling gas mayinclude, e.g., argon (Ar) or helium (He).

The gas injector may be configured to inject an oxidizing gas foroxidizing a metal layer on the substrate. The gas injector may include ashowerhead 200 having a plurality of injection holes 202 for injectingthe oxidizing gas onto or toward the substrate. The showerhead 200 maybe installed over (e.g., parallel with and facing) the substrate support120, and may inject the oxidizing gas through the injection holes 202. Agas supply 210 may be connected to the showerhead 200 to supply theoxidizing gas. In an implementation, the oxidizing gas may include,e.g., pure oxygen or a compound gas including oxygen.

In an implementation, a magnetic tunnel junction (MTJ) structure may beformed on the wafer W. The magnetic tunnel junction (MTJ) structure mayinclude a fixed layer structure, a tunnel barrier layer, and a freelayer that are sequentially stacked on the wafer W. In animplementation, a metal layer may be formed on the free layer. Thesubstrate processing apparatus 100 may be used for oxidizing the metallayer to form a metal oxide layer. A switching distribution of the freelayer may be improved by the metal oxide layer.

In an implementation, when the wafer W is kept at the extremely lowtemperature by the cooler, the oxidizing gas may be injected onto themetal layer via the injection holes 202 of the showerhead 200 to formthe metal oxide layer on the wafer W. Oxygen may have a tendency to bondwith the free layer. It may be desirable to help prevent the oxygen frommoving to the free layer when the free layer includes cobalt-iron-boron(CoFeB).

The cooler may be used to cool the electrostatic chuck 122 down to a lowtemperature, e.g., about 298K or less, by absorbing heat by a liquidrefrigerant. The wafer W may be moved onto the electrostatic chuck 122that is kept at the low temperature, and then fixed on the electrostaticchuck 122. For efficient heat transfer, the cooling gas, e.g. argon (Ar)or helium (He), may be injected into the cooling gas passage 304 of theelectrostatic chuck 122 to drop a temperature of the wafer W to a targettemperature. When the temperature of the wafer W reaches the targettemperature, oxygen gas may be uniformly injected toward the metal layervia the injection holes 202 of the showerhead 200 to form the metaloxide layer on the wafer W.

The metal oxide layer may be formed at the low temperature, and oxygenmay be prevented from penetrating into the free layer when forming themetal oxide layer. For example, defects due to oxygen migration into thefree layer may be reduced.

In an implementation, the substrate processing apparatus may performprocesses, which are performed in other cooling and oxidation chambers,in one chamber, thereby reducing footprint of chambers compared to othersubstrate processing systems.

FIG. 4 illustrates a cross-sectional view of a substrate processingapparatus according to some embodiments. The substrate processingapparatus may be substantially the same as or similar to the substrateprocessing apparatus described with reference to FIGS. 1 to 3 except fora gas injector.

Referring to FIG. 4, a gas injector of a substrate processing apparatus101 may include at least one gas nozzle 201 for injecting an oxidizinggas into a chamber 110.

In an implementation, the gas injector may include a plurality of gasnozzles 201 disposed around a substrate support 120. The gas nozzle 201may include a gas introduction portion extending upwardly from a lowersurface of the chamber 110, a nozzle portion having an injection hole203 from the gas introduction portion toward a wafer on the substratesupport 120.

The nozzle portion of the gas nozzle 201 may be provided over or facingthe substrate support 120, and may spray the oxidizing gas (foroxidizing a metal layer on the wafer W). A gas supply 210 may beconnected to the gas nozzle 201 to supply the oxidizing gas. In animplementation, the oxidizing gas may include, e.g., pure oxygen or acompound gas including oxygen.

FIG. 5 illustrates a plan view of a substrate processing systemaccording to some embodiments. FIG. 6 illustrates a cross-sectional viewof a substrate processing apparatus of the substrate processing systemof FIG. 5. FIG. 7 illustrates a perspective view of a gate in a housingof the substrate processing apparatus of FIG. 6. FIG. 8 illustrates across-sectional view of a showerhead moving together with the gate ofthe substrate processing apparatus of FIG. 6. The substrate processingapparatus may be substantially the same as or similar to the substrateprocessing apparatus described with reference to FIGS. 1 to 3, exceptthat it may further include a target mount and a blocker.

Referring to FIGS. 5 to 8, the substrate processing system 11 mayinclude a load lock chamber 20 for loading and unloading a substrate,such as a wafer, a transfer chamber 30 having a transfer robot 40 fortransferring the substrate, and a plurality of process chambers 60, 62,64 and 102. The transfer chamber 30 may be at a side of the load lockchamber 20. The plurality of process chambers 60, 62, 64 and 102 may beat sides of the transfer chamber 30.

In an implementation, the plurality of process chambers may include,e.g., a deposition/oxidation chamber 102, a first additional chamber 60,a second additional chamber 62, and a third additional chamber 64.

The deposition/oxidation chamber 102 may be a substrate processingapparatus for forming a metal layer on the wafer and for oxidizing themetal layer at a low temperature. Hereinafter, for convenience ofexplanation, the deposition/oxidation chamber 102 will be referred to asa substrate processing apparatus.

Referring to FIG. 6, the substrate processing apparatus 102 may includea substrate support 120, a cooler, a target mount 400, a gas injector,and a blocker. The substrate support 120 may be disposed in the chamberand include an electrostatic chuck 122 for supporting a substrate, suchas a wafer W. The cooler may be disposed below the electrostatic chuck122 and may cool the substrate. The target mount 400 may be disposedover the substrate. A target 410 for forming a metal layer on thesubstrate may be mounted on the target mount 400. The gas injector mayinclude a showerhead 200 for uniformly injecting an oxidizing gas. Theblocker may include a gate 500 that is configured to shield the target410 from being exposed to the oxidizing gas injected from the gasinjector.

In an implementation, the target mount 400 may be used for performing aphysical vapor deposition (PVD) process. For example, the target mount400 may be used to perform an RF sputtering process using an RF powersource. The target mount 400 may include a target holder 402 for holdingthe target 410.

The target mount 400 may include an RF power supply 420 that supplies RFpower to the target 410. The RF power supply 420 may supply a highfrequency signal to the target 410. The RF power supply 420 may bedisposed outside the chamber 110, and connected to the target 410. Thehigh frequency power may be, e.g., from about 400 KHz to about 40 MHz.

The blocker may include the gate 500 that serves as a shutter forshielding a specific area. The gate 500 may be disposed between thetarget 410 and the showerhead 200 of the gas injector.

In an implementation, the gate 500 may traverse an interior space of thechamber 110 between the target mount 400 and the substrate support 120,and may extend along a plane parallel to the wafer W on the substratesupport 120. For example, the interior of the chamber 110 may be dividedinto upper and lower chambers by the blocking unit including the gate500 according to an embodiment.

A housing 510 may be internally located at a central portion of thechamber 110. The housing 510 may include a sidewall portion 512 thatconstitutes a portion of a sidewall of the chamber 110. The sidewallportion 512 of the housing 510 may include an opening through which theupper and lower chambers communicate with each other.

The gate 500 may include a plate that has a shape corresponding to across-sectional shape of the chamber 110. The blocker may include adriver that is configured to move the gate 500 in the housing 510. Thegate may be installed to be movable along a plane parallel to the waferW in the housing 510 to selectively open and close the opening of thesidewall portion 512. For example, the gate 500 may shield the targetmount 400 from the lower chamber by moving into the chamber 110. Forexample, the gate 500 may be movable on the substrate support 120 to bebrought in or out of position between the target 410 and the wafer W.During a sputtering process, the opening of the housing 510 may beopened by the gate 500. After performing the sputtering process, theopening of the housing 510 may be closed by the gate 500.

The showerhead 200 may be installed under the gate 500. For example, theshowerhead 200 may be fixed to a lower surface of the gate 500 byfasteners. Thus, the showerhead 200 may be moved together with the gate500.

The gate 500 may be capable of reciprocating between a first position inwhich the gate 500 is located between the target 410 and the substratesupport 120, and a second position in which the gate 500 is locatedoutside the chamber 110. In the first position, the chamber 110 may beseparated into the upper and lower chambers by the gate 500, and in thesecond position, the upper and lower chambers may be communicated witheach other.

Referring to FIG. 8, when the sputtering process using the target 410 isperformed on the wafer W, the gate 500 may be moved from the firstposition to the second position. Referring to FIG. 6, when an oxidationprocess using the oxidizing gas is performed on the wafer W, the gate500 may be moved to the first position between the target 410 and thewafer W.

In an implementation, the sputtering process and the oxidation processmay be performed in-situ in one chamber. The oxidation process may beperformed at a cryogenic temperature. For example, when a metaloxidation layer is formed on a free layer of a magnetic tunnel junctionstructure, a switching distribution may be improved by preventing oxygenpenetration into the free layer. In an implementation, it is possible toreduce an area (or footprint) occupied by the chamber and to increaseunit per equipment hour (UPEH).

FIG. 9 illustrates a cross-sectional view of a substrate processingapparatus according to some embodiments. The substrate processingapparatus may be substantially the same as or similar to the substrateprocessing apparatus described with reference to FIGS. 5 to 8 except fora gas injector.

Referring to FIG. 9, a gas injector of the substrate processingapparatus 103 may include at least one gas nozzle 201 for injecting anoxidizing gas into a chamber 110.

In an implementation, the gas injector may include a plurality of gasnozzles 201 disposed around a substrate support 120. The gas nozzle 201may include a gas introduction portion extending upwardly from a lowersurface of the chamber 110, and a nozzle portion having an injectionhole 203 from the gas introduction portion toward a wafer on thesubstrate support 120.

The nozzle portion of the gas nozzle 201 may be provided on thesubstrate support 120, and may spray the oxidizing gas for oxidizing ametal layer formed on the wafer W. A gas supply 210 may be connected tothe gas nozzle 201 to supply the oxidizing gas. In an implementation,the oxidizing gas may include, e.g., pure oxygen or a compound gas thatincludes oxygen as a component thereof.

The gate 500 may be capable of reciprocating between a first position inwhich the gate 500 is located between the target 410 and the gas nozzle201, and a second position in which the gate 500 is located outside thechamber 110. In the first position, the chamber 110 may be separatedinto upper and lower chambers by the gate 500, and in the secondposition, the upper and lower chambers may be communicated with eachother.

When the sputtering process using the target 410 is performed on thewafer W, the gate may be in the second position. When the oxidationprocess is performed using an oxidizing gas, the gate 500 may be in thefirst position between the target 410 and the gas nozzle 201.

FIGS. 10 to 13 illustrate cross-sectional views of stages in a method offorming a memory unit of a magnetoresistance memory device according toexample embodiments.

Referring to FIG. 10, a lower conductive layer 620, a magnetic tunneljunction structure 660, and a metal layer 670 may be sequentially formedon a substrate 610.

The lower conductive layer 620 may include a metal and/or a metalnitride. The lower conductive layer 620 may include, e.g., a metal, suchas tungsten, titanium, or tantalum, and/or a metal nitride, such astungsten nitride, titanium nitride, or tantalum nitride.

The magnetic tunnel junction structure 660 may include a fixed layerstructure 630, a tunnel barrier layer 640, and a free layer 650, whichare sequentially stacked on the substrate 610.

In an implementation, the fixed layer structure 630 may include a fixedlayer, a lower ferromagnetic layer, an antiferromagnetic coupling spacerlayer, and an upper ferromagnetic layer.

The fixed layer may include, e.g., FeMn, IrMn, PtMn, MnO, MnS, MnTe,MnF₂, FeF₂, FeCl₂, FeO, CoCl₂, CoO, NiCl₂, NiO, or Cr. Each of the upperand lower ferromagnetic layers may include a ferromagnetic materialincluding at least one of iron (Fe), nickel (Ni), and cobalt (Co). Theantiferromagnetic coupling spacer layer may include, e.g., at least oneof ruthenium (Ru), iridium (Ir), and rhodium (Rh).

The tunnel barrier layer 640 may include, e.g., at least one of aluminumoxide or magnesium oxide.

The free layer 650 may include, e.g., a ferromagnetic material includingat least one of iron (Fe), nickel (Ni), and cobalt (Co).

In an implementation, the metal layer 670 may be formed on the freelayer 650 using the deposition chamber of FIG. 1 or the substrateprocessing apparatus of FIG. 5.

For example, referring to FIG. 8, the substrate 610, on which the freelayer 650 is formed, may be loaded on the electrostatic chuck 122 in thechamber 110. The gate 500 may be moved out of the first position(between the target 410 and the substrate) to the second position(outside the chamber 110). In an implementation, the metal layer 670 maybe formed on the substrate by performing a sputtering process using thetarget 410.

The metal layer 670 may include a metal having a large spin-orbitcoupling. In an implementation, the metal layer 670 may include, e.g., aheavy metal. In an implementation, the metal layer 670 may include,e.g., tungsten, tantalum, platinum, or bismuth.

Referring to FIG. 11, the metal layer 670 may be oxidized using thesubstrate processing apparatus of FIG. 1 or the substrate processingapparatus of FIG. 5 to form a metal oxide layer 672. For example, themetal oxide layer 672 may include a heavy metal oxide having a largespin-orbit coupling.

For example, referring to FIG. 6, the gate 500 may be moved to the firstposition between the target 410 and the substrate, and then, after atemperature of the substrate is cooled to a target temperature using thecooler, an oxidizing gas may be injected through the showerhead 200 touniformly oxidize the metal layer on the substrate. For example, a metaloxide layer may be formed on the substrate. The metal oxide layer may beformed at a cryogenic temperature, and oxygen may be prevented frompenetrating into the free layer when forming the metal oxide layer. Forexample, defects due to oxygen migration into the free layer may bereduced.

Referring to FIG. 12, an upper electrode 685 may be formed on the metaloxide layer 672.

The upper electrode 685 may be formed by patterning an upper electrodelayer that is formed on the metal oxide layer 672.

The upper electrode layer may include a metal and/or a metal nitride.The upper electrode layer may include, e.g., a metal, such as tungsten,titanium and tantalum, and/or a metal nitride, such as tungsten nitride,titanium nitride and tantalum nitride.

Referring to FIG. 13, the metal oxide layer 672, the magnetic tunneljunction (MTJ) structure layer 660 and the lower electrode layer 620 maybe sequentially etched by performing a dry etching process using theupper electrode layer 685 as an etch mask. The dry etching process mayinclude, e.g., an ion beam etching process or a sputtering process.

After performing the dry etching process, a lower electrode 625, amagnetic tunnel junction (MTJ) structure 665, a metal oxide pattern 675and the upper electrode 685 may be sequentially stacked on thesubstrate, and a conductive pattern 690 may be formed on at least aportion of a sidewall of the metal oxide pattern 675. The lowerelectrode 625, the magnetic tunnel junction (MTJ) structure 665, themetal oxide pattern 675, the conductive pattern 690 and the upperelectrode 685 may constitute a memory unit.

When the metal oxide layer 672 is etched by the etching process to formthe metal oxide pattern 675, a metal component included in the metaloxide pattern 675 may be redeposited on the sidewall of the metal oxidepattern 675, or the metal component and ions and/or particles used inthe etching process may be mixed with each other. In an implementation,the conductive pattern may be formed on the sidewall of the metal oxidepattern 675. A metal component of the upper electrode 685 may be alsoredeposited, or the ions and/or the particles may be also mixed with themetal component included the upper electrode 685.

Thus, the conductive pattern 690 may include the metal componentincluded in the metal oxide pattern 675 and/or the metal componentincluded in the upper electrode 685. The conductive pattern 690 mayinclude, e.g., tungsten, tantalum, platinum, bismuth, or titanium.

The memory unit may be formed through the above-described processesaccording to an embodiment.

By way of summation and review, a switching current density (Jc) in theMRAM device may be reduced with a view toward improving characteristicsof the MTJ structure. A metal oxide layer may be formed on the freelayer to help reduce the switching current density (Jc). According to anembodiment, a movement of oxygen to the free layer when forming themetal oxide layer may be suppressed.

The embodiments may provide a substrate processing apparatus for forminga thin film on a wafer and a method for manufacturing a magnetoresistiverandom access memory (MRAM) device with a magnetic tunnel junction (MTJ)structure using the same.

Example embodiments have been disclosed herein, and although specificterms are employed, they are used and are to be interpreted in a genericand descriptive sense only and not for purpose of limitation. In someinstances, as would be apparent to one of ordinary skill in the art asof the filing of the present application, features, characteristics,and/or elements described in connection with a particular embodiment maybe used singly or in combination with features, characteristics, and/orelements described in connection with other embodiments unless otherwisespecifically indicated. Accordingly, it will be understood by those ofskill in the art that various changes in form and details may be madewithout departing from the spirit and scope of the present invention asset forth in the following claims.

What is claimed is:
 1. A substrate processing apparatus, comprising: achamber accommodating a substrate; a substrate support in the chamber,the substrate support supporting the substrate; a gas injector to injectan oxidizing gas for oxidizing a metal layer to be disposed on thesubstrate; a cooler under the substrate to cool the substrate; a targetmount disposed on the substrate, the target mount including a target forperforming a sputtering process; and a blocker between the target andthe gas injector, the blocker shielding the target from the oxidizinggas injected from the gas injector.
 2. The substrate processingapparatus as claimed in claim 1, wherein the cooler: is in the substratesupport, and includes a cooling gas passage into which the cooling gasis flowed.
 3. The substrate processing apparatus as claimed in claim 1,wherein the cooler is operated to maintain the substrate at atemperature of less than about 298K when the oxidizing gas is injected.4. The substrate processing apparatus as claimed in claim 1, wherein thesubstrate support includes an electrostatic chuck for supporting thesubstrate.
 5. The substrate processing apparatus as claimed in claim 1,wherein the gas injector includes a showerhead for uniformly injectingthe oxidizing gas toward the substrate.
 6. The substrate processingapparatus as claimed in claim 5, wherein the oxidizing gas includes pureoxygen or a compound gas that includes oxygen.
 7. The substrateprocessing apparatus as claimed in claim 1, wherein the blocker: ismovably installed between the target and the substrate support, andincludes a gate that is capable of opening and closing a space betweenthe target and the substrate support.
 8. The substrate processingapparatus as claimed in claim 7, wherein: the gas injector includes ashowerhead for injecting the oxidizing gas, and the showerhead isfixedly installed under the gate.
 9. The substrate processing apparatusas claimed in claim 7, wherein the gate is movable such that the gate isnot in a position between the target and the substrate when thesputtering process is performed using the target and is in the positionbetween the target and the substrate when an oxidation process isperformed using the oxidizing gas.
 10. A substrate processing apparatus,comprising: a chamber accommodating a substrate; a substrate support inthe chamber, the substrate support supporting the substrate; a coolerunder the substrate to cool the substrate; a gate disposed to be movableon the substrate support in the chamber and operated to selectivelydivide the chamber into upper and lower chambers; a gas injector toinject an oxidizing gas for oxidizing a metal layer on the substrate;and a target mount facing the substrate and including a target forperforming a sputtering process.
 11. The substrate processing apparatusas claimed in claim 10, further comprising a blocker between the targetand the gas injector, wherein the blocker shields the target from theoxidizing gas injected from the gas injector.
 12. The substrateprocessing apparatus as claimed in claim 10, wherein the gas injectorinclude a showerhead that is fixedly installed on a lower portion of thegate.
 13. The substrate processing apparatus as claimed in claim 10,wherein the gate is movable such that the gate is not in a positionbetween the target and the substrate when a sputtering process isperformed using the target and is in the position between the target andthe substrate when an oxidation process is performed using an oxidizinggas.
 14. The substrate processing apparatus as claimed in claim 10,wherein the cooler is operated to maintain the substrate at atemperature of less than about 298K when the oxidizing gas is injected.15. The substrate processing apparatus as claimed in claim 10, wherein:the substrate support includes an electrostatic chuck for supporting thesubstrate, and the electrostatic chuck is in direct contact with acooling surface of the cooler.
 16. A substrate processing apparatus,comprising: a chamber in which a substrate is accommodatable; asubstrate support in the chamber and on which the substrate issupportable, the substrate support including a cooler therein; a targetmount facing the substrate support, the target mount including a targetfor performing a sputtering process that forms a metal layer on thesubstrate, a gas injector to inject an oxidizing gas that oxidizes themetal layer on the substrate; a blocker between the target and the gasinjector, the blocker shielding the target from the oxidizing gas. 17.The substrate processing apparatus as claimed in claim 16, wherein thecooler cools the substrate when the oxidizing gas is injected by the gasinjector.
 18. The substrate processing apparatus as claimed in claim 16,wherein the gas injector includes a showerhead that uniformlydistributes the oxidizing gas onto the substrate.
 19. The substrateprocessing apparatus as claimed in claim 16, wherein the blocker: ismovably installable between the target and the substrate support, andincludes a gate that is capable of separating a space between the targetand the substrate support.
 20. The substrate processing apparatus asclaimed in claim 19, wherein: the gas injector includes a showerheadthat uniformly distributes the oxidizing gas onto the substrate, and theshowerhead is fixedly installed on a substrate-facing side of the gate.